Pneumocystis jirovecii (P. jirovecii) is an atypical fungus that can cause severe interstitial pneumonia in immunocompromised patients. In this study, mitochondrial large subunit ribosomal RNA (mtLSU-rRNA) and dihydropteroate synthase (DHPS) gene polymorphism in P. jirovecii isolates were investigated in Western Turkey's Izmir province and its surroundings. For this purpose, a total of 157 P. jirovecii isolates obtained from bronchoalveolar lavage samples of hospitalized cases and lung tissue samples of autopsy cases who died outside hospital were examined. Genotypes were identified by direct sequencing of mtLSU-rRNA restriction fragment length polymorphism analysis of the DHPS gene amplicons. The mtLSU-rRNA analysis revealed that genotype 2 was the most common genotype with 58%. The following genotypes were genotype 3 (13%), genotype 1 (11.6%) and genotype 4 (5.1%), while genotype 5 (0.7%) was detected in only one autopsy case. In addition, 16 (11.6%) cases had dual or triple different genotypes (mixed infection). It was observed that the genotype distribution was not affected by characteristics such as age, gender and immune status. However, the predominance of genotype 2 in solid organ tumors and the predominance of mixed infection in patients with chronic pulmonary disease were statistically significant. On the other hand, DHPS gene amplification was positive in 137 (87.3%) of 157 samples. While no mutation was observed in 135 samples, the association of wild-type and 57th codon mutation was detected in two hospitalized cases (1.5%). In this study, important epidemiological data on the distribution of mtLSU-rRNA genotypes were obtained. Also the existence of DHPS gene mutations associated with potential drug resistance in our community was shown for the first time. Further studies are needed to evaluate the possible effects of genotypes on the prognosis of the disease to help with the clinician's treatment decisions. Lay abstract Pneumocystis jirovecii (P. jirovecii) is an atypical fungus that can cause life-threatening pneumonia in immunocompromised patients. In this study, we investigated the mtLSU-rRNA and DHPS gene polymorphisms in P. jirovecii isolates from both hospital and autopsy cases.

中文翻译：

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基于线粒体大亚基核糖体 RNA 和二氢蝶酸合酶基因分型的土耳其人群耶氏肺孢子菌遗传多样性

Pneumocystis jirovecii (P. jirovecii) 是一种非典型真菌，可在免疫功能低下的患者中引起严重的间质性肺炎。在这项研究中，在土耳其西部伊兹密尔省及其周边地区调查了 P. jirovecii 分离株的线粒体大亚基核糖体 RNA (mtLSU-rRNA) 和二氢蝶酸合酶 (DHPS) 基因多态性。为此，对从住院病例的支气管肺泡灌洗液样本和在院外死亡的尸检病例的肺组织样本中获得的 157 株 P. jirovecii 分离株进行了检查。通过 DHPS 基因扩增子的 mtLSU-rRNA 限制性片段长度多态性分析的直接测序鉴定基因型。mtLSU-rRNA 分析显示基因型 2 是最常见的基因型，占 58%。以下基因型为基因型 3 (13%)、基因型 1 (11. 6%）和基因型 4（5.1%），而基因型 5（0.7%）仅在一个尸检病例中检出。此外，16 例（11.6%）病例具有双重或三重不同基因型（混合感染）。据观察，基因型分布不受年龄、性别和免疫状态等特征的影响。然而，基因2型在实体器官肿瘤中的优势和慢性肺病患者中混合感染的优势具有统计学意义。另一方面，157个样本中有137个（87.3%）DHPS基因扩增呈阳性。虽然在 135 个样本中未观察到突变，但在两个住院病例（1.5%）中检测到野生型和第 57 位密码子突变的关联。在这项研究中，获得了有关 mtLSU-rRNA 基因型分布的重要流行病学数据。此外，我们社区首次显示存在与潜在耐药性相关的 DHPS 基因突变。需要进一步的研究来评估基因型对疾病预后的可能影响，以帮助临床医生做出治疗决策。Lay abstract Pneumocystis jirovecii (P. jirovecii) 是一种非典型真菌，可在免疫功能低下的患者中引起危及生命的肺炎。在这项研究中，我们调查了来自医院和尸检病例的 P. jirovecii 分离株中的 mtLSU-rRNA 和 DHPS 基因多态性。jirovecii) 是一种非典型真菌，可在免疫功能低下的患者中引起危及生命的肺炎。在这项研究中，我们调查了来自医院和尸检病例的 P. jirovecii 分离株中的 mtLSU-rRNA 和 DHPS 基因多态性。jirovecii) 是一种非典型真菌，可在免疫功能低下的患者中引起危及生命的肺炎。在这项研究中，我们调查了来自医院和尸检病例的 P. jirovecii 分离株中的 mtLSU-rRNA 和 DHPS 基因多态性。